US PATENT SUBCLASS 257 / 551
.~.~ Including voltage reference element (e.g., avalanche diode, so-called "Zener diode" with breakdown voltage greater than 6 volts or with positive temperature coefficient of breakdown voltage)

Current as of: June, 1999
Click HD for Main Headings
Click for All Classes

Internet Version by PATENTEC © 1999      Terms of Use


257 /   HD   ACTIVE SOLID-STATE DEVICES (E.G., TRANSISTORS, SOLID-STATE DIODES)

499  DF  INTEGRATED CIRCUIT STRUCTURE WITH ELECTRICALLY ISOLATED COMPONENTS {9}
544  DF  .~ With pn junction isolation {8}
551.~.~ Including voltage reference element (e.g., avalanche diode, so-called "Zener diode" with breakdown voltage greater than 6 volts or with positive temperature coefficient of breakdown voltage)

DEFINITION

Classification: 257/551

Including voltage reference element (e.g., avalanche diode, so-called "Zener diode" with breakdown voltage greater than 6 volts or with positive temperature coefficient of breakdown voltage):

(under subclass 544) Subject matter including a voltage

reference element, i.e., a device which limits the operating voltage of one or more active devices in the integrated circuit (e.g., an avalanche diode, so-called "Zener diode" with breakdown voltage greater than 6 volts, or with positive temperature coefficient of breakdown voltage).

SEE OR SEARCH THIS CLASS, SUBCLASS:

199, for an avalanche diode in a non-charge transfer device having a heterojunction.

481, and 482, for Schottky barrier avalanche diodes.

603, through 606, for avalanche diodes not classified above those subclasses in this schedule, i.e., not involving a heterojunction in a non-charge transfer device or a Schottky barrier, or one used as a voltage reference element with pn junction isolation means in an integrated circuit.